The Clinical Epilepsy Section has been studying the clinical pharmacology of old and new antiepileptic drugs. In spite of the fact that many older medications have been marketed for many years, there is still a great deal to be learned about the proper use of these drugs which are already in our armamentarium. The Clinical Epilepsy Section is also actively involved in clinical trials of new antiepileptic drugs, such as sodium valproate, which was recently marketed in the United States, and a compound called progabide, which is completely new to the United States. This drug is being tested for epilepsy in eight European.